The Pentagon announced Friday morning that it had conducted its first round of strikes on Islamic State (which also goes by ISIS or ISIL) targets. Officials told NBC News that U.S. Navy fighter jets based on a carrier in the Persian Gulf had dropped bombs on Islamic State artillery.

A State Department spokeswoman said on Twitter that some of the U.S. attacks on ISIS targets near Erbil were conducted by unmanned aircraft against a mortar position.

In a White House press briefing Friday afternoon Press Secretary Josh Earnest said that the U.S. would conduct strikes to protect American personnel, prevent humanitarian crises, or to help unite Iraqi security forces against the ISIS insurgents.

"If there is a role for the American military to play in supporting the Iraqi people and that inclusive government, and an integrated security force that is capable of defending the country, then we'll use that American military prowess in pursuit of that goal as well," Earnest said.

Earnest also stressed that President Barack Obama is opposed to involving U.S. troops in ground combat, and that he does not believe the situation in Iraq can be solved solely by American military involvement. Still, Earnest said, the president has not set a specific end date for military operations in the country.